It is well known to provide a lathe comprising a rotary driven chuck for holding and rotating a workpiece, a tool carrying turret mounted for movement both longitudinally of the axis of rotation of the chuck and about an axis extending transversely of the rotation axis of the chuck so as to permit different tools mounted on the turret to be brought into cutting engagement with the workpiece, and a cross slide mounted for movement transversely of the rotation axis of the chuck, the cross slide being adapted to have mounted thereon a cutting tool which is movable by the cross slide into cutting engagement with the workpiece to cut a peripheral groove therein.
A lathe of this kind is particularly suited to preprogrammable automatic operation, but suffers from the disadvantage that a tool on the cross slide can only cut in the workpiece a groove of a width defined by the width of the tool, and moreover the width of the tool which can be used is restricted by the fact that a small diameter workpiece tends to get broken or bent by the cutting engagement of a wide tool with the workpiece.